In a gas turbine, a combustion chamber, in particular an annular combustion chamber or a silo combustion chamber, has at least one burner, in particular a premix burner. In particular embodiments of the combustion chamber, a burner of this type may be equipped with a lance which extends through a passage opening formed in a head of the burner and projects into the burner. A lance of this type serves to inject fuel into the burner or into the combustion chamber.
In the region of the abovementioned passage opening, the lance has to be sealed with respect to the burner in order to prevent the hot combustion exhaust gases from penetrating into a space upstream of the burner. A seal of this nature must be sufficiently elastic to enable it to cope with the relative movements between lance and burner that occur when the combustion chamber is operating. These movements are firstly vibrations which occur while the combustion chamber is operating and secondly extreme thermal expansion or contraction effects which occur when the combustion chamber or gas turbine is being run up and shut down. Finally, the seal has to be able to withstand the high temperatures which occur in operation.